Classical Gas was written and publicized by Mason Williams in 1968 - still nimble and able, Mason Williams still performs it (as do many other players), but in addition to being an all-around good player, Williams was a driving force behind the Smothers Brothers Comedy Hour (and hiring 22 year-old Steve Martin) and he als...well, let him tell you.
E-Bow A nifty electric guitar effect that replaces the pick. Ignore the visuals. Instead, give it a listen.
Musical instruments are pretty good examples of form following function. Over time, they evolve into standard shapes. Occaisionally, some people push the instruments in new directions. Other times, they run at right angles to reality